查询词典 vegetation

The water resources change is a leading factor in the vegetation degeneration there; The swamp vegetation was based on the background of large-scale lakes and rivers; the halophyte meadow was based on the background of dry lakes and riverside, and desert vegetation was based on the background of desert; desert vegetation was based on the background of desert at present.

水资源的变化是决定当地植被退化的主导因子，在大面积湖泊、河流背景上是沼泽植被，在干涸湖泊、河床背景上的是盐生草甸植被，在沙质荒漠背景上的是荒漠植被。

As a result of case study in Haidian district, Beijing, the accuracy rate of vegetation fraction estimation by using "dense vegetation model" and "nondense vegetation model" synchronously based on land cove classification is obtained about 75.4%, which is 5.8% higher than that of using "dense vegetation model" only.

根据TM像元为非均一混合像元的特点，提出了基于土地覆盖分类的综合运用"等密度模型"和"非密度模型"计算植被覆盖率的方法，通过对北京市海淀市区的植被覆盖率计算表明，该方法的估算精度可达75.4%，比单纯使用等密度亚像元模型在估算精度上可提高5.8%。

Secondly, According to the sub-pixel structure characteristic, the potential of deriving vegetation fraction from normalized difference vegetation index using the TM data and resorting to "Dense Vegetation Model" and "Nondense Vegetation Model", is studied in an area in the south of Yichang.

本文首先对TM影像进行了几何纠正、辐射校正、大气校正；然后根据混合像元的结构特征，利用TM数据从植被指数中采用"等密度模型"和"非密度模型"提取了宜昌南部地区的植被覆盖度。

Some researchers believe that the latter area possesses savanna vegetation. Savannas are closely associated with seasonal drought, and they may be defined by climatic climax vegetation in tropical and subtropical areas. Based on the ecoclimatic analyses as well as the surviving vegetation in Taiwan, we inferred that the potential natural vegetations of these 2 semi-arid regions were not savanna but forest with some drought-deciduous trees. In conclusion, the physiognomic type of grassland dotted with trees may occur in small areas at present, but Taiwan lacks climate-shaped savanna climax vegetation.

本研究将疏林定义为分布於热带及亚热带之气候形塑的极相植群，气候分析结果表明台湾半乾旱区域之缺水逆境并不严重，再配合现生残存植群之观察，发现台湾有形相为疏林的现生局部性植群，但其潜在自然植群应为参杂有乾旱落叶之阔叶树种的森林，并不存在较大面积之潜在的气候型极相疏林。

The main study areas are as follows: 1 The landscape classification system of the urban-rural ecotone is set up based on the studying on land-use type of urban area and rural area, and then it is used to establish a regional landscape data warehouse for deposition, modification and management; 2 A group of landscape structure and pattern indices and patch area spectrum analysis methods are used to describe the structural and heterogeneous characters of all the landscape elements from different aspects; 3 The temporal and spatial difference of the landscape pattern of main road belts of the research area are also analyzed with the same method. Their basic process and regularity of urban axial expanding of the southwestward of Shanghai City are initially knewn well; 4 According to the traits of the ecotone, the principles and basis of vegetation classification, the ecotone vegetation classification system is set up, its species constitute, community patch characters, the relationship between vegetation types and landscape categories are analyzed, meanwhile, the vegetation sample maps are made; 5 Based on above studies, some landscape ecological stratedies within the research area were discussed. The following are the results of this study

城乡交错带地区的景观分类，在对城市地区和农村地区的土地利用类型研究的基础上建立了城乡交错带的分类体系，并在此基础上用ARC＼INFO软件分时段、分区、分要素建立研究区的景观图形数据库，对数据进行存储、修改和管理；2）利用多种景观结构、格局指数和斑块面积谱分析方法，从不同的侧面对各种景观组分的结构以及区域的景观格局特征进行了分析，并对其成因进行了探讨；3）利用相同的分析方法，分析了城乡交错带中的城市干道两侧的景观格局特征的空间和时间分异情况，初步掌握上海城市西南轴向扩张的基本过程和规律；4）对城乡交错带中非独立的景观要素-植被，研究其遥感图象信息的基本特征，建立适合区域特点的植被分类体系，并在样区中建立了植被图形数据库和计算机制图，分析了植被景观种类组成、斑块等级等特征以及与不同景观的相互关系；5）在上述研究的基础上，对研究区内的景观生态对策进行了研究。

Based on the meteorological observation data and the vegetation index data in Yulin,synchronousness relationship of vegetation index and sandstorm activities were analyzed,the results indicates that,Intra-annual changes of vegetation covers and sandstorm activities are evidently inverse synchronous,which may conduce to reducing the wind-break and sand-fixing function of vegetation.

以榆林市为例，利用气象观测和植被指数数据，对植被覆盖与沙尘暴活动发生的时间同步性关系进行了分析，结果显示：植被覆盖与沙尘暴活动存在着年内的时间不同步性，严重制约植被防风固沙生态功能的发挥；沙尘暴日数与植被指数的年际变化呈现出反相关系证明了植被覆盖对沙尘暴活动具有很强的防护作用。

The following results are made from this research: Assessing data quality and band combination of different bands in line with geo-target features in desertification areas, and determining basic bands for desertification monitoring. And understanding and studying the spectral features and variation rules of geo-targets in the experimental area, raising that it is the basis of geo-targets information collection with imaging spectrometer data to understand spectral features and variation rules of geo-targets, realizing that in a great extent spectral-integrated-form-based classification method can remove the phenomenon of "different spectrum with same objects" resulted from reflection ratio curve translation because of the angle change among sensor, targets and observation direction, and the average and variance images can be introduced to solve the problem of two kinds of geo-target with similar spectral forms and much different values of whole reflectionratio. It is suggested that "red edge" range bands of vegetation, which has close relationship with vegetation cover and biomass, is the main characteristic bands and important basis for careful vegetation classification and quantitative retrieval, and pixel-based derivative spectral analysis is very useful for removing the effects of soil background values and quantitatively retrieving vegetation biomass and cover. The remote sense quantitative retrieval model is developed for main appraisable factors of desertification monitoring assessment with imaging spectrometer data and then the applicability of model is analyzed.

研究结果如下：首先针对荒漠化地区的地物特征，对高光谱数据不同波段的数据质量、波段组合进行了评价，提出了适用于荒漠化监测的基本波段选择集；初步了解和掌握了研究地区的地物光谱特性及变异规律，进一步明确了掌握地物光谱特征和变异规律是用成像光谱仪数据提取地物信息的基础；发现了基于光谱整体形状的分类方法在很大程度上能够消除由于传感器、地物目标观测方向之间的角度变化引起的反射率曲线整体平移的"同物异谱"现象，对于谱形相似而整体反射率的值相差较大的两类地物，通过引入均值和方差图像参与分类得到解决；研究还表明在植被"红边"范围内的波段是进行荒漠化监测的主要特征波段，这些波段与植被生物量和盖度都有密切的关系，是开展精细植被分类研究和植被定量反演的重要基础；像元的导数光谱分析可以消除土壤背景的影响，是进行植被生物量和盖度定量反演的有力工具；建立了荒漠化监测主要评价因子的定量反演模型，并分析了模型的适用性。

The following results are made from this research: Assessing data quality and band combination of different bands in line with geo-target features in desertification areas, and determining basic bands for desertification monitoring. And understanding and studying the spectral features and variation rules of geo-targets in the experimental area, raising that it is the basis of geo-targets information collection with imaging spectrometer data to understand spectral features and variation rules of geo-targets, realizing that in a great extent spectral-integrated-form-based classification method can remove the phenomenon of "different spectrum with same objects" resulted from reflection ratio curve translation because of the angle change among sensor, targets and observation direction, and the average and variance images can be introduced to solve the problem of two kinds of geo-target with similar spectral forms and much different values of whole reflectionratio. It is suggested that "red edge" range bands of vegetation, which has close relationship with vegetation cover and biomass, is the main characteristic bands and important basis for careful vegetation classification and quantitative retrieval, and pixel-based derivative spectral analysis is very useful for removing the effects of soil background values and quantitatively retrieving vegetation biomass and cover. The remote sense quantitative retrieval model is developed for main appraisable factors of desertification monitoring assessment with imaging spectrometer data and then the applicability of model is analyzed.

研究结果如下：首先针对荒漠化地区的地物特征，对高光谱数据不同波段的数据质量、波段组合进行了评价，提出了适用于荒漠化监测的基本波段选择集；初步了解和掌握了研究地区的地物光谱特性及变异规律，进一步明确了掌握地物光谱特征和变异规律是用成像光谱仪数据提取地物信息的基础；发现了基于光谱整体形状的分类方法在很大程度上能够消除由于传感器、地物目标观测方向之间的角度变化引起的反射率曲线整体平移的&同物异谱&现象，对于谱形相似而整体反射率的值相差较大的两类地物，通过引入均值和方差图像参与分类得到解决；研究还表明在植被&红边&范围内的波段是进行荒漠化监测的主要特征波段，这些波段与植被生物量和盖度都有密切的关系，是开展精细植被分类研究和植被定量反演的重要基础；像元的导数光谱分析可以消除土壤背景的影响，是进行植被生物量和盖度定量反演的有力工具；建立了荒漠化监测主要评价因子的定量反演模型，并分析了模型的适用性。

The achievement of this project can be briefly summed up as following:(1)the carbon contributing to karst processes mainly comes from ecological system itself under the condition of existence of vegetation and soil covers;(2)results indicates that the depositing processes of rainfall to CO2 is an important "sink" to global carbon cycle;(3)owing to the differences of vegetation and surface covering, the adjusting effect of ecosystem to environmental humidity, temperature and CO2 concentration near surface air which indicates different benefit of preventing water and soil from lose is marked;(4)the preponderant species of vegetation in the karst ecosystems which have different kinds of carbonate rocks are obviously variant, and this situation results to the clearly differences of the micro － habitat , structure of surface cover and water holding capacity;(5) the relevant study showed that the carpophagous animals and birds make a important role in the spreading of vegetation seeds. The designed experience for the study of seed reservoir was not able to obtain a satisfactory result.

主要研究成果包括：通过对表层系统碳库的研究，认为在有土壤和植被覆盖时，岩溶作用过程中的碳主要来自生态系统本身而不是母岩；降雨对大气碳具有重要&沉淀&作用，是碳的一个重要汇；不同植被类型表层岩溶系统对系统水份、空气湿度、气温、土温和近地表 CO2浓度等具有明显调节作用，具有不同的水土保持效益；不同母岩的岩溶生态系统的植被优势种、属差异明显，由此形成的小生境、地被物及其持水性差异巨大；对典型岩溶表层系统种子库的试验研究没有取得满意结果，但食果动物、鸟类对种子传播起到一定作用。

The results in these three regions have been given that (1) Ephedra, as dry and desert vegetation, the average percents are 7.7 in Yang Lake, 4.2 in Kunlun Rive, 7.5 in Doucuo Lake, and the datum in Yang Lake is higher than others;(2) Gramineae, as humid vegetation, the average percents are 1.2 in Yang Lake, 4.9 in Kunlun Rive, 12.0 in Kuhai Lake, increasing gradually from west to east;(3) Artemisia, as humid vegetation, the average percents are 22.2 in Yang Lake, 43.6 in Kunlun Rive, 48.8 in Kuhai Lake, increasing gradually from west to east, too;(4) Chenopodiaceae, as dry vegetation, the average percents are 52.1 in Yang Lake, 42.4 in Kunlun Rive, 11.5 in Kuhai Lake, however, decreasing gradually from west to east;(5) Artemisia/Chenopodiaceae ,the average data, as environmental changing index, are 0.45 in Yang Lake, 1.23 in Kuniun Rive, 5.59 in Kuhai Lake, increasing gradually from west to east, and there is higher data scope during 3.0~4.3 ka BP in these two lake sediment profiles, then decreasing;(6) Ephedra/Artemisia, data are all increased but the amplitude is different, such as 0.45 in Yang Lake, 0.34 in Kunlun Rive, 0.28 in Kuhai Lake, decreasing gradually from west to east.

代表气候湿润的禾本科花粉平均百分含量，三个地区分别为：1.2%、4.9%、12.0%，从西向东数值逐渐升高。③代表气候湿润的蒿属花粉平均百分含量，三个地区分别为：22.2%，43.6%，48.8%，从西向东数值逐渐升高。④代表气候干旱的草科花粉平均百分含量，三个地区分别为：52.1%，42.4%，11.5%，从西向东数值逐渐降低。⑤依据蒿属、藜科花粉百分含量，计算出环境变化指标，蒿属／藜科值，三个地区的平均值分别为：0.45，1.23，5.59，从西向东比值逐渐升高，⑥麻黄属／蒿属值，在全新世晚期，三个地区都呈上升趋势，但幅度存在差异，分别为：0.45，0.34，0.28，从西向东数值逐渐降低。

This matter overthrew all basises I learned from Sunday school .

这件事把我从周日学校学到的所有道理都颠覆了。

It's one of the cruel ironies of aging: if you want to remember your favorite restaurants, the less you should eat at them.

这是一个老化的残酷讽刺：如果你想记住你最喜欢的餐馆，你应该更少吃到它们。